Effect of correlation on electronic properties of NiO: A study from dynamical mean field theory

Abstract

In order to describe a typical strongly correlated insulator NiO at electronic level, we perform a first principles calculation for temperature effect on electronic properties of NiO using a many-body method merging local density approximation (LDA) with dynamical mean field theory, so called the LDA+DMFT scheme. Band gap and density of states (DOS) are in good agreement with available experimental data and theoretical calculations, and Ni d-eg and d-t2g components both exhibit insulating character. Calculated hybridization functions indicate that Ni d-eg states strongly hybrid with O p states at T = 58 K, 116 K, 145 K, 232 K and 464 K. In order to compare with experimental angle-resolved photoemission spectrum (ARPES), we also calculate momentum-resolved electronic spectrum function, which is established that obvious electronic excitation mainly arises from Ni d-t2g states at temperature T = 232 K, and the spectrum functions between −0.5 eV and 0.0 eV are almost symmetric about certain k points. Finally, we analyze the effect of temperature on electronic properties of NiO by carrying out LDA+DMFT calculations at T = 58 K, 116 K, 145 K, 232 K and 464 K, respectively. Results show that temperature mainly influences the valence states of spectrum function and hybridization function, in particular high-lying states close to Fermi level. Electronic excitation distributions and spectrum characters in electronic spectrum function are also discussed.